A North Long Beach aerospace supplier is the latest metal finishing facility being forced to reduce its emission of a hexavalent chromium, a carcinogen linked to lung cancer.

An administrative board on Thursday ordered Lubeco, Inc., to curtail the release of chromium-6 to prevent any harm to residents and children at a nearby school.

It is the third metal finishing company in several months forced to reduce emissions or shut down some operations. The actions come after air district officials found high levels of the carcinogen in nearby Paramount last year.

“We expect this order to help protect the health and safety of residents in this area,” said Wayne Nastri, head of the South Coast Air Quality Management District.

Air regulators recorded the cancer-causing substance at 18 times above normal levels in the air near Lubeco between May 13 and July 12. The average level of chromium-6 in the air near the company was 1.07 nanograms per cubic meter. That’s compared to the base average of 0.6 nanograms per cubic meter.

Regulators argued the elevated readings endangered public health and should be brought down.

The district has launched a campaign to crack down on other metal processing companies believed to be emitting the toxic substance.

Air regulators targeted the industry after elevated levels of chromium-6 emissions were traced back to processes used to strengthen metal.

Regulators found the carcinogen when metals were dunked in certain heated chemicals, a common practice in the industry.

Officials at Lubeco said the company will comply with the orders and in emission controls.

“The facility is committed to protecting the environment and their compliance history demonstrates that,” said Bruce Armbruster, environmental consultant at the Long Beach company.

“The district just learned these tanks, formerly never regulated, were an issue,” he said. “As soon as they did, the facility took immediate to take these tanks out of service or put in air pollution control devices.”

Under the order, Lubeco must ensure that readings of chromium-6 do not exceed 1 nanogram per cubic meter, based on a three sample average.